The invention discloses a method for encrypting communication of a power system debugging tool based on a shared secret key. Under the existing shared-key mechanism, all communication environments usethe same key pair, and there is a risk that the malicious attacker can reverse-analyze the key by acquiring a large number of communication samples. The invention presets a shared initialization keyKInt and a shared key group KG, and agrees on the same encryption and corresponding decryption algorithm. In the communication process, the initiator and the receiver use the initialization key KInt to realize the mechanism that the communication key KT is specified by the receiver by checking the random number, and the mechanism that the initiator and the receiver agree to confirm the communication key together, so as to realize the method that the two sides use different shared key for each communication, and to improve the security of the encrypted communication.